5/7/2010

Finally got around to the promised post on energy solutions and futures.

First up, even if we leave aside the issue of climate change entirely, fossil fuels are finite resources.

(Barring a few fantasies about endless renewal from currently on-going natural processes (someone posted a link on that here a while ago and I emailed the scientist who did the original research and she was very definitive that its a tiny source and definitely not the source of the reserves we’re using now)).

So whether we start cutting down on our use now or in a couple of decades, we will definitely have to cut down some time.

What I’m suggesting here is that we get a head start.

I’m absolutely, 100%, not talking about decimating economies and standards of living, anywhere in the world. The goal of this approach is humanitarian, definitely, but that goal is not zero-sum. It is to extend to those in the developing world the lifestyle and health benefits that those of us in the developed world have gained on the back of the massive gift of cheap energy we got from fossil fuels. At the same time, it is to guarantee our own lifestyles into the future, because without action they are unsustainable.

It was the world’s inheritance, and we’ve spent most of it. I’m not about guilt for that, but I am about the responsibility to use that boost to now offer benefits to those who missed out in the first rush (which is really not much more than a century old).

So please leave aside your fantasies of the ravening socialist horde coming to force you to live in a cave. They’re just that, dark fantasies.

First point: Any approach needs to be multifaceted. Fossil fuels, particularly oil, gave us ‘magic-bullet’ solutions to all sorts of problems from powering cars, planes and trains to lubricating their moving parts and generating electricity. We don’t get it that easy again.

Second point: Any solution for the foreseeable future will still have both coal and oil as components. That’s one reason it’s important to conserve them. (The other is petrochemicals like plastics: our descendants will be aghast that we burned something is incredibly useful as petroleum.) It’s a fantasy from the green side to think we can wean ourselves off fossil fuels entirely in the near term.

But what we do need to do is make huge steps to replace them as the mainstays of our energy use. Here are several possible facets of a solution:

(this one is related to climate change, the rest are not) Coal reserves are huge – much greater than oil. There are dirty approaches to converting coal into gas or oil, but they are wasteful and expensive. A better approach is to use the coal to produce electricity, then the electricity to produce hydrogen for a hydrogen economy (see below). This all works and is all proven technology right now. The other piece of the picture is carbon sequestration: the benefit of burning coal in a power station versus burning it in a vehicle is that it’s a lot easier to capture the emitted carbon dioxide and store it underground. That way we can keep using this valuable resource without completely trashing our environment. (Coal is also a very ‘dirty’ fuel in terms of things like the sulfur that causes acid rain: the sequestration process can capture these too.)

A hydrogen fuel cell economy. Hydrogen is an energy transport technology, not an energy production technology, but it’s clean and powerful. In cars it would be adsorbed onto metal hydrides in tanks, with *less* explosion and fire risk than tanks of gasoline. Hydrogen itself would not need to be transported in tankers, because it could be made in fuel cells in filling stations, using electricity: and we already have electricity infrastructure. It’s better than battery for cars because no charge cycle is required – you can just drive in and fill up as you do now – and also because it doesn’t require heavy, environmentally costly batteries. To his credit, President G W Bush pushed hard for the hydrogen economy.

Nuclear fusion is the long term solution. It’s probably 40 years away at the moment, but that could be shortened with increased research funding. Despite the word ‘nuclear’, fusion produces no radioactive waste, and the fuel supply is essentially limitless. Fusion would in many ways create an energy utopia, with enough for all our terrestrial needs many times over, and enough hydrogen for a dramatically expanded space program too.

Nuclear fission is an essential part of a short term solution. I know this is an issue on which I part company with many of my fellow ‘greens’, but I think it’s unavoidable. Opposition to the waste and risk of fission was the principled position 20 and 30 years ago, but that was before (a) massive improvements in plant safety, (b) dramatically better approaches for waste handling and storage and (c) before we knew about the real environmental costs of fossil fuels. I am really, truly actively suggesting the building of many more fission power plants all around the world. It’s not a perfect technology, but it’s a crucial part of the bridge to get us to fusion.

Renewables. All of these draw on solar power to some extent (except tidal, which draws on the gravitational force of the moon). A calculation I made recently for a textbook chapter I’m writing:

The solar energy reaching the top layers of earthâ€™s atmosphere is about 1400 W per square metre. Of that energy, only about 40% makes it down to the earthâ€™s surface â€“ the rest is reflected back to space (about 30%) or absorbed by the atmosphere, heating it directly (the remaining 30%).

So take the 40% that makes it to the surface: 560W/sqm. Imagine that’s only over half the earth at a time, so make it 560W/sqm over half the earth’s total land surface area (because collecting the solar energy over the oceans is tougher, although hydroelectricity actually does that) of 150 million square metres, and you get 42 billion watts – about 3 times all human energy use on earth. And that calculation is conservative at all levels.

Hydroelectricity: dams, lots of them. And yeah, greens tend to stop dams being built to protect environments and species. We can do some of that, but we have to build dams. They have the added effect of protecting fresh water reserves, another essential infrastructure for humanity.

Solar, both photovoltaic and concentration forms. Scalable, ubiquitous, and cheaper and more efficient all the time. New approaches are being developed all the time, and putting in the research will help to deal with the current problems. If every new house was, as a matter of course, roofed with solar panel material, that in itself would be an immense change. Creating huge solar farms in otherwise unusable land like areas of outback Australia and African deserts also has a lot of potential.

Wind. It’s a myth that wind farms kill birds. They are noisy, but that’s partly a technology issue, and there are plenty of uninhabited windy places. In Holland they put them out to sea.

Tidal. Only works in some places, but useful.

Wave – an immense untapped resource.

Geothermal – useful in some regions.

Ocean thermal – using cold deep water and warm surface water with a heat pump.

All of these can be used to generate electricity, feeding into a hydrogen economy. None of them is a magic bullet due to issues like day/night, windy/not windy and so on, but they don’t need to be if we work toward a complementary set of solutions rather than rubbishing them individually because they don’t provide a complete solution.

Ones I’ve forgotten. Please feel free to add your own!

Ones that haven’t even been invented yet, but could be if the basic research was done. Computers have revolutionised our lives, but were really invented within the lifetimes of some of those who post here. The next big thing may be hiding just around the corner. That’d be great, but we shouldn’t and don’t need to rely on it, because we already have all of the proven technologies outlined above that, if combined, could solve this thing.